<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>

    <div id="app">
       <!-- <div v-if="isShow == true">
           账号登陆
           <input type="text" placeholder="请输入账号">
           <button @click="btnClick">切换</button>
       </div>
       <div v-else>
        邮箱登陆
        <input type="text" placeholder="请输入邮箱">
        <button  @click="btnClick">切换</button>
    </div> -->

    <span v-if = "isUser">
        <label for="username">用户账号</label>
        <input type="text" id="username" placeholder="用户账号">
    </span>
    <span v-else>
        <label for="email">用户邮箱</label>
        <input type="text" id="email" placeholder="用户邮箱">
    </span>
    <button @click="isUser = !isUser">切换类型</button>

    </div>
    <script src="../js/vue.js"></script>
    <script>
        const app = new Vue({
            el:'#app',
            data:{
                message:'你好呀！',
                isShow:true,
                isUser:true,
            },
            methods:{
                btnClick(){
                    this.isShow = !this.isShow
                }
            }
        })
    </script>
</body>
</html>